None.
Not Applicable.
This invention relates in general to an improved method for transferring an image onto an object having curved surfaces. More particularly, this invention relates to an improved method for effecting thermal transfer of an image onto a surface which is generally convex in two directions.
In U.S. Pat. No. 5,832,819, which is incorporated herein by reference, a method for transferring an image onto an object having curved surfaces is described. Generally, the method comprises the steps of providing a photograph, photocopy or other graphical representation (hereinafter referred to as a source) having thereon an image capable of thermal transfer, placing the source against an object having curved surfaces so that the image is aligned with a target surface, pressing the source until the target surface is substantially flat, and then heating the source to a temperature between 350 and 750 degrees Fahrenheit (depending on the target surface) so that the image is transferred to the target surface. If the object is a vinyl covered baseball, the preferred temperature is between 475 and 525 degrees Fahrenheit.
The method described in U.S. Pat. No. 5,832,819 effectively transfers an image to an object. There was a concern with the method, however, relating to the fact that the temperature at which the transfer occurs often is significantly higher than the melting point of the object. Specifically, the high transfer temperature makes the timing of the process critical because deviation in that timing may lead to the object melting.
In an effort to reduce the likelihood of damage to the object, several additional steps were investigated. After some time, it was decided that the best additional step was to submerse the heated object in cold water or alcohol immediately after the image is transferred. Unfortunately, while this submersion step worked well, it also caused a significant delay in the process so that the object could be dried. With the addition of a submersion step, and the subsequent drying, the process for transferring an image onto a baseball took as long as seven to ten minutes.
It was therefore undertaken to provide an improved method of transferring an image onto an object that has a surface that curves in two directions which does not employ temperatures that may damage the object and which was both efficient and cost-effective. One area that was investigated was to determine if a substance applied to the object would allow the image to adhere at a lower temperature. In order to be effective, the substance would have to be clear so that the appearance of the object would not change, be able to bond with the object without separating, be flexible so that it would not crack or disfigure when the object was flattened, and be heat resistant so that it would not melt when heat was applied.
After considerable research, a chemical coating was discovered that satisfied these needs. Specifically, it was discovered that if the chemical coating was properly applied to the target surface, the image would transfer quickly at a significantly lower temperature. For example, with the chemical coating properly applied, an image could be transferred onto a baseball if the source was subjected to a temperature between 190 and 200 degrees Fahrenheit for as little as 15 seconds. This temperature and time was sufficient to protect the baseball from melting, and, therefore, the submersion step with the resultant drying was no longer required.
Research continued in an attempt to further improve the method, and specifically, to determine if steps could be undertaken to decrease the vulnerability of an image to scratching and other damage after the image had been transferred. This research revealed that heating the image a second time after the image had been transferred to the object would xe2x80x9csetxe2x80x9d the image. In addition, the second application of heat had the effect of giving the image a crisper, more professional appearance. The research also revealed that using a heat gun to accomplish this second heating was too slow and uncertain. Instead, the image needed to receive heat directly.
Thereafter, it was determined that directly pressing the image a second time with a heating element effectively drove the image into the object although the heating element required cleaning afterwards. Also, using the heating element directly against the object raised the risk that the object would be damaged. After further research, it was found that placing a protective material between the heating element and the image for at least the second heating would cause the image to be driven into the surface of the object while preventing the image from transferring back to the heating element. Careful selection of the protective material also insured that the image would not attach to the material.
With the added steps of applying a chemical coating to the target surface before transferring the image and inserting a protective material between the object and the heating element before applying heat to the image a second time reduced the time it took to produce a finished product from seven to ten minutes to one minute or less. In addition, the final product would have a more professional appearance.
The present invention discloses an improved method for transferring an image onto an object which has a surface that curves in two directions. After providing a source containing an image capable of thermal transfer, a target surface is chosen on the object and a chemical coating is applied. The image is then pressed into the coated target surface until the target surface is substantially flat and heated so that the image is transferred to the target surface. The coating allows the image to be transferred at a low temperature. In a preferred embodiment, after the source is removed, a second application of heat is applied to the object to drive the image into the object. A protective material may be positioned between the heating element and the image, especially before the second application of heat.